J
js5895
- Jan 1, 1970
- 0
Hi,
I'm studying electrical, what's the best way to remember the P.I.R.E.
wheel.
Thanks.
I'm studying electrical, what's the best way to remember the P.I.R.E.
wheel.
Thanks.
js5895 said:Hi,
I'm studying electrical, what's the best way to remember the P.I.R.E.
wheel.
Learn just one formula such as V=IR and rearrange terms mathematically
as needed. No escaping the math if you want this field.
Roger Johansson said:Pedantic mode on.
You have to learn _two_ equations, actually.
V=I*R (Volt=Amp*Ohm)
P=U*I (Watt=Volt*Amp)
Then learn how to re-arrange these equations as needed for the problem
at hand, and use a calculator to get the result.
The art of re-arranging equations is called algebra, and you need some
basic knowledge and experience in this.
An alternative is to use a visual diagram like the ones I have put on a
web site
http://humanist.250free.com/
Click on the two .jpg files at the bottom of the list, save them to
hard disk. Can be distributed freely.
js5895 said:Hi,
I'm studying electrical, what's the best way to remember the P.I.R.E.
wheel.
Thanks.
Can someone sum up the top couple of rules of algebra for him? How
about something like: 'An equation has an expression on each side of
the equal sign. To solve the equation for any of the variables, you
need to get that variable over to the left side of the equal sign. To
eliminate a variable on one side, multiply both sides of the equation
by the inverse of that variable. This doesnt change the equality,
because you are multiplying both sides by the same number.' Is this the
necessary and sufficient information needed to solve ohms law for 3
variables?
Peter Bennett said:I use three rules:
1. If you do something on one side of the equal sign, you must do the
same thing on the other.
2. Anything divided by itself equals 1.
3. Anything multiplied by 1 is unchanged, so the "1" can be discarded.
I've been working in electronics for some 40 years, and have no idea
what the "P.I.R.E. wheel" is - I just remember E = IR and P=EI, and
shuffle things around as needed. The same "shuffling" rules apply to
any simple equation.
BobG said:Can someone sum up the top couple of rules of algebra for him? How
about something like: 'An equation has an expression on each side of
the equal sign. To solve the equation for any of the variables, you
need to get that variable over to the left side of the equal sign. To
eliminate a variable on one side, multiply both sides of the equation
by the inverse of that variable. This doesnt change the equality,
because you are multiplying both sides by the same number.' Is this
the necessary and sufficient information needed to solve ohms law for
3 variables?
Peter said:I've been working in electronics for some 40 years, and have no idea
what the "P.I.R.E. wheel" is - I just remember E = IR and P=EI, and
shuffle things around as needed. The same "shuffling" rules apply to
any simple equation.
js5895 said:Thanks, I know basic high school algebra, but I just never understood
how to apply it to real world problems. I keep reading my electrical
book on that it says "Current is directly proportional to voltage" and
"Current is inversely proportional to resistance" and then I look at
the
P.I.R.E. wheel, trying to remember the whole wheel just by remembering
those statements and some algebra. I'm looking at it like a puzzle and
noticing some patterns like, that the power formulas you have to square
or square root to find an answer, so I can see that proportional and
inversely proportional part. I'm trying to figure out how they got
something like this "I = E/R" from that statement, looking at that
formula, thinking "I" is proportional to "E" and "I" is inversely
proportional "R", and I'm thinking why did they divide?. I'm racking my
mind and I know this is a simple basic DC formula compared to other
electrical formulas like, the AC ones.
js5895 said:Thanks, I know basic high school algebra, but I just never understood
how to apply it to real world problems. I keep reading my electrical
book on that it says "Current is directly proportional to voltage" and
"Current is inversely proportional to resistance" and then I look at
the
P.I.R.E. wheel, trying to remember the whole wheel just by remembering
those statements and some algebra. I'm looking at it like a puzzle and
noticing some patterns like, that the power formulas you have to square
or square root to find an answer, so I can see that proportional and
inversely proportional part. I'm trying to figure out how they got
something like this "I = E/R" from that statement, looking at that
formula, thinking "I" is proportional to "E" and "I" is inversely
proportional "R", and I'm thinking why did they divide?. I'm racking my
mind and I know this is a simple basic DC formula compared to other
electrical formulas like, the AC ones.
I can add some to your text above.
You can do anything to an equation as long as you do it to both sides
equally, the equation is still valid.
(an exception is dividing by zero, which gives meaningless results)
The methods you can use to isolate one variable on one side are
addition, subtraction, multiplication, division, inverting, squaring,
square root, substitution, etc..
Somebody who does not know these methods should take some time to learn
basic algebra, especially equation solving.
An online equation solver, for really lazy people
Thanks, I know basic high school algebra, but I just never understood how
to apply it to real world problems. I keep reading my electrical book on
that it says "Current is directly proportional to voltage" and "Current is
inversely proportional to resistance" and then I look at the
P.I.R.E. wheel, trying to remember the whole wheel just by remembering
those statements and some algebra. I'm looking at it like a puzzle and
noticing some patterns like, that the power formulas you have to square or
square root to find an answer, so I can see that proportional and
inversely proportional part. I'm trying to figure out how they got
something like this "I = E/R" from that statement, looking at that
formula, thinking "I" is proportional to "E" and "I" is inversely
proportional "R", and I'm thinking why did they divide?. I'm racking my
mind and I know this is a simple basic DC formula compared to other
electrical formulas like, the AC ones.
wheel.js5895 said:Hi,
I'm studying electrical, what's the best way to remember the P.I.R.E.
No escaping the math if you want this field.
phaeton said:Re-teaching myself Algebra is obviously a requirement, but will I need
to teach myself anything like Calculus? Trigonometry?